• Restorative Dentistry and Endodontics
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• v.19 no.2
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• pp.585-601
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• 1994

The purpose of this study was to evaluate the ability of several intracoronal base materials to prevent cervical leakage of a bleaching agent into the dentinal tubules and along the root canal. In this study, thirty-two anterior teeth were used. After lingual access was prepared in each tooth, tooth was instrumented with a step-back technique to a Nos. 40-50 using K-type files. All teeth were obturated with a lateral condensation technique. Excess gutta percha was removed with a warm instrument to the facial level of the CEJ. Teeth were divided into four groups : Teeth in control group were not filled with base material. Teeth in groups 1, 2, and 3 had 2mm of gutta percha removed with a warm instrument, then Dycal, Fuki II LC and Z-100 were filled with palstic instruments on the top of the gutta percha respectively. All teeth were bleached for 7 days, fresh bleach was added for another 7 days, then a 10 % methylene blue dye was placed inside the access preparation. They were stored at $37^{\circ}C$ and $100^{\circ}C$ humidity for 5 days. Each tooth was sectioned perpendicular to the long axis using a diamond disk. Initial cuts were made at the most coronal level of facial and lingual CEJ's, then another cuts continued appically in the levels of 0.5mm, 1.5mm, and 2.0mm respectively. The amount of dye leakage through the dentinal tubules was determined at each cut section. In addition, when the cut specimen was determined to be last penetration of any dye, this level was recorded as depth of apical leakage from the coronal terminus of the gutta percha, Dycal, Fuji II LC and Z-100. The acquired data were analyzed by Tukey's Multiple Range Test adn Cochran-Mantel-Haenszel Test to see if there was any statistically significant difference in dye penetration and linear apical leakage among the groups. The results were as follows : 1. Control group at levels of CEJ and 0.5mm, group 3 at level of 1.5mm, and group 2 AND 3 at level of 2.0mm showed the least dye penetration through the facial or lingual dentinal tubules, but there were no significant difference among three groups. 2. Group 2 at levels of CEJ and 0.5mm, group 3 at level of 1.5mm, and group 2 and 3 at level of 2.0mm showed the least dye penetration through the proximal dentinal tubules, but there were no significant difference among control group, group 2, and group 3. 3. Group 1 showed the greatest dye penetration through the facial or lingual and proximal dentinal tubules at all levels, and there were significant difference with other three groups. 4. Control group and group 1 showed 2mm apical dye leakage at facial or lingual and proximal aspects, group 2 showed 1.5mm, and group 3 showed 0.5mm.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.2
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• pp.100-104
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• 2013

Zoysiagrass (Zoysia japonica Steud.) is an important forage and turfgrass that spreads by stolons and rhizomes. Zoysiagrass stolon can be used directly for Agrobacterium-mediated genetic transformation by exploiting the potential of direct shoot formation. However, surface sterilization of field-grown stolons is difficult and remains to be explored. We developed an effective surface sterilization and culture method using the stolon explant for infection with Agrobacterium tumefaciens. Among various treatments, sequential disinfection in 30% bleach for 15 min followed by 0.1% mercuric chloride for 25 min resulted in the highest number of clean stolons. The efficacy of mercuric chloride was increased under vacuum conditions by incubating at 800 mbar for 5 min. The inclusion of 2.5 mg/l amphotericin B further prevents fungal growth in in vitro cultures. This protocol would speed up the development of transgenic plants by utilizing field-grown stolon nodes.

• Archives of design research
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• v.2 no.1
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• pp.13-41
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• 1989

The raw materials for plant-stalk-folkcrafts are cultivated in the whole country. Most Korean farmers, to increase their income, have produced mats and containers with various plants as a side line from very long ago. At first, they began from the instruments of life and then made folkart and at last get to manu\ulcornerfacturing of industrial folk craft. The folkcrafts, made of plant-stalk, which could nor conform to changing society, are partly declined and partly handed down as the traditions. The social change today, however, makes living conditions more speedy and multisided, accordingly the characteristics of demand also become in\ulcornerdividual and various. While the demend is various like this, suppliers cannot answer demendants' requirements, and consequently, the demand and profit cannot be increased. According to this, the purpose of this study is set up to give an answer to the situation that is at the traditional standstill, through an examination of the motives. I. The crafts of plant-stalk are made only in an organized relationship between agriculture, industry and art as it is compounded art of gathering raw material, manufacturing, producing, improv\ulcornering design and production conditions. It may be possible that a farmer gathers material and weaves it manually but in others, it is im\ulcornerpossible to refine, bleach and dye because the process requires a professional industrial treatment. It is impossible to make art works to a farmer as every farner does not always have aesthetic sense. Though a farmer or producer has these all abilities, it is not desirable to him from economical view. 2. The development or improvement is essential in many sides but the most important thing seems to he in design. According to reports, it is, howevt!r, fact that the crafts improved in design of existing works have more expanded the sales than newly developed works. Therefore, ir appears advisable to improve designs of existing things positively as they have merit of occupying a position already, but on the other hand, new crafts have to be also developed and the producer should grasp the proper time. 3. Building up an industrial complex to improve design with collecting the producing districts for this works scattered allover the country is very desirable for speedy communication, intensive educa\ulcorner tion or training, and effective guidance. 4. In producing for export abroad, before everything, must know the life environment, custom! and manners, main thought of the country, and then produce according to these. S. The crafts of plant-stalk are the fIrst industry in present but in the futher it should change intc second or third industry. 6. A synethetic organization for supporting side line should be established for effectiveness, and experts have to be secured and also the educational-industrial complex and activation of study should be preceded.

• Journal of the Korean Home Economics Association
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• v.19 no.2
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• pp.11-24
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• 1981

The objectives of the study were to determine 1) if energy consumption and conservation vary in clothing, food, and housing with independent variables-size of household, homemaker's age, employment, and level of education, level of living, type of house, electricity use, and all energy use, and 2) if there is a correlation among energy conservation practices in clothing, food, and housing. Questionnaires wee given to the randomly selected homemakers in Seoul in July, 1980. Data from 620 responses were analyzed by F-test (Analysis of Variance) and Correlation. The results are as follows: 1. Clothing (1) the scores of the conservation practices I clothing were generally high. /However, it was found that a) they did not practice in wearing heavy under clothes and behavior outer clothing to cope with cool room temperature in the winter, b) they did not use bleach for laundry, but they used boiling method, and c) they did not have enough knowledge on Permanent Press finish. (2) energy conservation practices in clothing were significantly related to level of living and homemakrer's level of education. a) The higher the level of living, the higher scores in the knowledge were found. b) the higher the homeakcer's level of education, the higher scores in the knowledge and ironing were obtained. 2. Food (1) The scores of the conservation practices in food were generally high. However, it was found that scientific cooking methods were not performed such as a) to use measuring spoons, cups, and timers, b) to practice a simple method in using solor energy for warming water, c) to use thermos for the hot water tea or coffee, but they boiled water whenever necessary, and b) to use the pressure cooker whenever possible. (2) Energy conservation practices in food were significantly related to homemaker's employment and type of dwellings. a) The scores of full-time homemakers (not gainfully employed) were higher than gainfully employed homemakers. b) Families in traditional Korean dwellings revealed higher scores than those in apartment or western style dwellings. 3. Housing (1) The scores of the conservation practices in housing were generally high. However, it was found that a) they did not install fans in the kitchen, bathroom, and attic in the summer, b) they did not install a humidifier for tolerating a lower room temperature in the winer, c) they did not practice to make plans for the door of the refrigerator remained open for the shortest time, d) they did not install or use a local lighting with a general lighting for reading and cooking, and e) they usedaluminum foil without the knowledge of the heat reaction of its shiny and dull sides. (2) energy conservation practices in housing were significantly related to homemaker's employment and level of education, economic status, types of dwelling, and all energy use, a) Full-time homeakers had higher scores than gainfully employed homeakers. b) the higher the homemaker's level of education and economics status, the higher scores were obtained. c) Homeakers with their own house scored higher points than those with rented houses. And families in apartment or row houses scored higher points than those in traditional korean or western style dwellings. d) The higher the consumption rate of electricity and all energy, the higher scores were revealed. 4. correlation there was a significant correlation among energy conservation practices I clothing, food, and housing.

• Korean Journal of Ecology and Environment
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• v.54 no.3
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• pp.247-256
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• 2021

Understanding the selective feeding behavior of zooplankton on phytoplankton is essential for evaluating the nutrient cycle and energy flow in the food web. Although many studies have been conducted regarding the feeding behaviors of zooplankton through gut content analyses, there are limitations in the visual identification of digested contents using a microscope. DNA techniques have been applied to overcome these limitations since they can detect and amplify small amounts of prey DNA remaining in the gut contents. We designed a method to extract prey DNA from the gut contents of the whole body of the copepod specimen and tested the resolution of DNA identification for the prey phytoplankton. The common brackish species, Sinocalanus tenellus, were collected from Saemangeum Reservoir in different sites and seasons, and gut content DNA was extracted using 2.5% bleach treatment for 2 min for removal of potential contamination sources existing in preserved specimens without dissolution of the body. The sequences of the extracted gut contents were confirmed using BLASTn suite based on the NCBI database. The phytoplankton species detected in the gut showed temporal and spatial differences. Although DNA analysis of small copepod gut contents has been suggested as an effective method to examine the dynamics of primary prey sources at the genus or species level, uncertainties such as misidentification and limitations in the detailed information of the composition still exist.